All actual evidence suggests that the friction between stylus and groove is NOT a major cause of static charge build up on the LP surface. To begin with, Shure Corporation published a study of electrostatic charge during vinyl playback and found no evidence for a cause-effect relationship. But as someone else pointed out, Shure did not publish actual data to support their conclusion, whereas they did publish data to support most of their other results. So these expensive devices that you point at the LP while it is playing in order to prevent or remove static charge while it accumulates are probably a waste of money, not because they don’t work at all but because such a device is not needed. If the surface is discharged prior to play by any of many simpler and cheaper devices like the Zerostat, it will remain discharged during play. So what makes me so convinced of that proposition? I too was dubious of the Shure claim, so I bought an ES charge meter off eBay. You can buy a nice one for under $200. First I demonstrated to my own satisfaction that the meter works as advertised. Then I charged up an LP surface by rapidly removing it from its paper sleeve. The meter told me that its charge was -11,000V from that action. I then discharged the surface using the Zerostat as it is supposed to be used and one of the requirements is to hold the LP in your hands in space. One pass with the Zerostat reduced the charge to -100V (LPs accumulate negative charge, so the minus sign is for real). I then played that LP and again measured the charge immediately after play. It read -200V. Charge that low in magnitude is near the lower limits of the accuracy of the meter (the meter is graduated in kilovolts, so 100V appears as 0.1kV, for example), so I do not think the difference between -200V and -100V is necessarily real. Nor do I think a charge of -200V is consequential compared to -11,000V. In any case, removing the LP from its paper sleeve was about 100 times more effective in inducing a charge than playing the LP. Since then I have repeated the experiment several times, with similar results. As for mats or other magic potions that reduce or eliminate static charge, I am agnostic. Felt mats would seem to me to be a bad idea, however.
So why, you may ask, doesn’t the friction between stylus and groove cause static? Diamond is a good donor of electrons and vinyl is a good acceptor, so you would think the friction ought to be a cause of static charge buildup. I don’t know the answer to that question, but my hypothesis is that the tiny magnetic field present in the vicinity of the motor of any MM, MI, or MC cartridge might suck up any electrons flying around in that micro environment. One test for my idea would be to run a modified cartridge that lacks the generator parts, has only a stylus on a suspended cantilever but nothing on the other end of the cantilever. The question to ask then is whether that castrated cartridge can induce a static charge during a pass across an LP surface.
I think the major causes of static charge on LPs is the act of removing them from a paper or similar sleeve and the act of touching the LP while we ourselves are bearing a charge that then leaks onto the LP. Also, Shure did show and did publish data to show that when you discharge one surface of the LP, that charge can leak over to the side of the LP that is against the mat. This could be why we sometimes note that the LP sticks to the mat or that there is a crackling sound as we remove the LP from the platter.
